High-transmittance glass, forming method thereof, laminated glass and vehicle window glass

Abstract

The invention provides high-transmittance glass, a forming method thereof, laminated glass and vehicle window glass. The forming method comprises the following steps: placing a glass sheet in a heating furnace for heating treatment, and then carrying out compression molding to obtain the high-transmittance glass, the heating furnace comprises a preheating section, a heating section and a constant-temperature transition section which are sequentially connected; the inlet temperature of the preheating section is 592-632 DEG C, the outlet temperature of the preheating section is 613-647 DEG C, and the outlet temperature of the preheating section is higher than the inlet temperature; the inlet temperature of the heating section is 630-664 DEG C, the outlet temperature of the heating section is 648-674 DEG C, and the outlet temperature of the heating section is higher than the inlet temperature; the temperature of the constant-temperature transition section is 653-677 DEG C; the inlet temperature of the heating section is larger than or equal to the outlet temperature of the preheating section, and the inlet temperature of the constant-temperature transition section is larger than or equal to the outlet temperature of the heating section. The high-transmittance glass has the advantages of light weight, high light transmittance, high mechanical strength, high scratch resistance and high wear resistance.

Description

Technical Field

[0001] The invention relates to the field of vehicle window glass manufacturing, and in particular to a high-transmittance glass and a molding method thereof, a laminated glass and a vehicle window glass. Background Art

[0002] The raw materials used for automobile glass, especially the front windshield, are generally automobile-grade raw materials produced by float glass process. Automobile-grade raw materials include: ordinary white glass (Clear, referred to as C), green glass (Green, referred to as G), heat-absorbing green glass (SolarGreen, referred to as SG) and super heat-absorbing green glass (SolarDark, referred to as SD).

[0003] At present, the bump area of ​​automotive glass, especially the front windshield, integrates more and more optical sensor elements. These optical sensors have higher and higher requirements for the front windshield, such as LiDAR, infrared cameras, etc., which require the maximum optical transmittance in the corresponding near-infrared band, such as 800-1600nm. The existing automotive glass raw sheets cannot meet the requirements, and glass raw sheets with low absorption and high transmittance in the corresponding band are needed. In addition, with the popularization and application of new energy vehicles, the requirements for lightweight are becoming more and more obvious, and the same is true for car window glass, so there is a need to improve the lightweight of automotive glass.

[0004] For functional integrated windshields, such as LiDAR built-in products, glass sheets with low absorption and high transmittance optical properties in the corresponding band are required; at the same time, the thickness of the glass sheets needs to be appropriately thinned to meet the lightweight requirements; in addition, while maintaining the original optical properties and strength of the glass sheets, it is also necessary to improve the glass sheets' ability to resist scratches and wear.

[0005] The molding parameters of low-absorption and high-transmittance glass sheets are different from those of existing automobile glass sheets, and a molding method for this type of glass sheets needs to be provided. Summary of the invention

[0006] In order to solve the above problems, the purpose of the present invention is to provide a high-transmittance glass and its forming method, laminated glass and vehicle window glass. The high-transmittance glass has low absorption and high light transmittance, can meet the requirements of optical sensors for optical transmittance, and can be used in the manufacture of functional integrated glass; while the thickness is reduced, it can maintain high strength, meeting the requirements of lightweight automotive glass.

[0007] In order to achieve the above object, the present invention provides a method for forming high-transmittance glass, the forming method comprising:

[0008] The glass raw sheet is placed in a heating furnace for heating treatment, and then pressed into shape to obtain the high-transmittance glass; the heating furnace comprises a preheating section, a heating section, and a constant temperature gradient section which are connected in sequence; the inlet temperature of the preheating section is 592-632°C, the outlet temperature of the preheating section is 613-647°C, and the outlet temperature of the preheating section is higher than the inlet temperature; the inlet temperature of the heating section is 630-664°C, the outlet temperature of the heating section is 648-674°C, and the outlet temperature of the heating section is higher than the inlet temperature; the temperature of the constant temperature gradient section is 653-677°C; the inlet temperature of the heating section is greater than or equal to the outlet temperature of the preheating section, and the inlet temperature of the constant temperature gradient section is greater than or equal to the outlet temperature of the heating section.

[0009] In the above-mentioned forming method, the preheating section is used to heat the glass sheet in the first stage, the heating section is used to heat the glass sheet in the second stage, and the constant temperature gradient section is used to keep the glass sheet warm and transfer it to the subsequent process. The preheating section and the heating section can be roughly divided according to the softening temperature of the glass sheet. The heating temperature of the glass sheet in the preheating section is generally lower than the softening temperature of the glass sheet, and the heating temperature of the glass sheet in the heating section is generally higher than the softening temperature of the glass sheet. Therefore, the glass sheet begins to soften after entering the heating section. It can be understood that in actual production, the heating temperature of the heating furnace is generally not equal to the heating temperature of the glass. Therefore, the heating temperature of each section of the heating furnace can be adjusted accordingly based on the softening temperature range of the glass, as long as the heating degree is reached so that the glass is heated in the preheating section but does not begin to soften, and begins to soften after entering the heating section.

[0010] In the present invention, the softening temperature of the glass sheet refers to the temperature at which the glass begins to deform or soften under the action of its own weight. For example, the softening temperature of low-absorption and high-transmittance glass sheets such as medium-aluminum glass sheets is around 625°C. The softening temperature of glass is generally 100-120°C lower than its softening point. The softening point refers to the temperature at which the glass begins to deform or soften under certain conditions. The softening point can be measured by the Littleten glass fiber vertical extension method, and the process is as follows: the heating suspension density is 2.5g / cm 3 When the glass fiber is about 0.55-0.75mm in diameter and 229mm in length, the temperature when it is stretched at a speed of 1mm / min is the softening point.

[0011] In the above molding method, the heating rate of the preheating section is 0.08-3.0°C / s.

[0012] In the above molding method, the heating rate of the heating section is greater than 0°C / s and less than or equal to 2.4°C / s.

[0013] In some specific embodiments, the heating rate of the preheating section may be greater than or equal to the heating rate of the heating section. The temperature change range in the constant temperature gradient section is small and the heating rate is very small, and the heating rate of the constant temperature gradient section is generally smaller than the heating rates of the preheating section and the heating section.

[0014] In the above-mentioned forming method, the heating method of each section (preheating section, heating section, constant temperature gradient section) can be a common heating method such as uniform heating, variable heating, step heating, etc. The present invention has no special limitation on the heating method.

[0015] The present invention divides the heating furnace into three main heating treatment sections according to function: a preheating section, a heating section, and a constant temperature gradient section. Each section can be further divided according to the actual situation of the equipment (such as the position and number of heating components such as heating wires in the heating furnace). The present invention has no special restriction on the number of further divisions of the preheating section, the heating section, and the constant temperature gradient section, as long as the heating scheme of each section (such as heating temperature, heating rate, etc.) can be realized.

[0016] The molding method of the present invention is further described below by taking a heating furnace having 9 partitions as an example:

[0017] In the above-mentioned forming method, the heating furnace may specifically have 9 heating zones, and the heating zones from the sheet inlet end to the sheet outlet end of the heating furnace are the first zone to the ninth zone in sequence, the first zone to the third zone are preheating sections, the fourth zone to the seventh zone are heating sections, and the eighth zone to the ninth zone are constant temperature gradient sections; from the first zone to the ninth zone, the heating temperature gradually increases (the overall trend is an upward trend, and the situation where the temperatures of adjacent heating zones are similar is not excluded, for example, the temperatures of the seventh zone, the eighth zone, and the ninth zone can be close); each heating zone heats the glass original sheet from the top and bottom of the glass original sheet at the same time;

[0018] Among them, the heating temperatures of the first zone, the second zone and the third zone are 592-647°C respectively, the heating temperatures of the fourth zone, the fifth zone and the sixth zone are 630-668°C respectively, and the heating temperatures of the seventh zone, the eighth zone and the ninth zone are 648-677°C respectively.

[0019] According to a specific embodiment of the present invention, the glass raw sheet applicable to the above-mentioned molding method provided by the present invention is a low-absorption, high-transmittance glass raw sheet. Ordinary glass raw sheets have a high iron content (for example, the iron content of ordinary white glass is 700-900ppm, the iron content of ordinary green glass is 5000ppm, and the iron content of absorbed green glass is about 7000ppm). The iron content of the glass raw sheet applicable to the present invention is lower, generally below 150ppm, further below 130ppm or below 110ppm, and further below 90ppm; the iron content is the weight content of iron oxide. The lower the iron content, the lower the absorption of the glass raw sheet.

[0020] In addition, the aluminum content (weight ratio of aluminum oxide) of ordinary glass sheets is generally less than 1wt%; the glass sheet applicable to the molding method of the present invention can be medium aluminum glass, and the aluminum content can reach 4-5wt%. The above aluminum content can improve the stability and mechanical strength of the glass and increase the toughness of the glass; at the same time, it can also ensure that the glass sheet can soften during the molding process. In the prior art, medium aluminum glass is usually used as electroplated glass for touch screens of mobile communication devices. The present invention improves the molding process of medium aluminum glass so that it can be used as automotive glass, reduces the weight of the glass, and improves the scratch and wear resistance of automotive glass.

[0021] In some specific embodiments, the softening point temperature of ordinary glass sheets is about 725-730°C, and the softening point temperature of the glass sheets applicable to the present invention is relatively high, which can be 742-752°C; the annealing point temperature of the glass sheets applicable to the present invention is generally 550-570°C, that is, the softening point temperature is more than 30% higher than the annealing point temperature (such as 30%-37%). The softening point temperature of the glass sheets applicable to the present invention is proportional to the annealing point temperature. The higher the softening point temperature, the higher the corresponding annealing point temperature. In the above-mentioned molding method of the present invention, the heating temperature of the first zone can be higher than the annealing point temperature of the glass sheets.

[0022] In some specific embodiments, the aluminum glass raw sheet used in the present invention can be, but is not limited to, glass raw sheets from the following sources: A aluminum glass raw sheet, which includes the following components by mass fraction: 73%-76% SiO 2 4%-6% Al 2 O 3 2%-3% B 2 O 3 , 6%-8% CaO, 2%-4% MgO, 9%-12% Na 2 O, 0.1-0.3% CeO 2 , 0-0.1% Sb 2 O 3 The aluminum-aluminum glass raw sheet can be made by the following process: mixing the raw materials meeting the above composition with water, smelting (1560-1600°C, 3-4h), clarifying (1430-1480°C, 1-2h), cooling (1150°C-1220°C) and rolling by rolling rollers, annealing (70°C-560°C, 10min-20min), and obtaining the glass raw sheet.

[0023] In the above-mentioned molding method, the thickness of the glass sheet used can be less than 2.1 mm, and further can be less than 1.8 mm, for example, 1.3-1.8 mm, 1.3-1.6 mm. The glass sheet of the present invention can be comparable to the thickness of the ordinary glass sheet, or it can be thinner than the ordinary glass sheet (thickness of about 2.1 mm). When the thickness of the glass sheet used in the present invention is reduced relative to the ordinary glass sheet, the high-transmittance glass obtained after molding has the characteristics of lightweight, which can meet the requirements of the automobile manufacturing field for lightweight. In a specific embodiment, the heating temperature of the aluminum-aluminum glass sheet can be adjusted according to the thickness of the glass sheet. Generally speaking, as the thickness of the aluminum-aluminum glass sheet increases, the heating temperature increases accordingly.

[0024] In some specific embodiments, the glass raw sheet used in the present invention can be obtained through a float glass production process, such as an electronic grade float glass production process.

[0025] In the above forming method, the light absorption coefficient of the glass sheet to light with a wavelength of 800-1600nm can be 0.04-0.2cm -1 , for example 0.04cm -1 、0.05cm -1 、0.06cm -1 、0.07cm -1 、0.08cm -1 、0.09cm -1 、0.10cm -1 、0.11cm -1 、0.12cm -1 、0.13cm -1 、0.14cm -1 、0.15cm -1 、0.16cm -1 、0.17cm -1 、0.18cm -1 、0.19cm -1 , 0.20cm -1 The light absorption coefficient may be 0.04-0.11 cm -1 .

[0026] In the present invention, the light absorption coefficient refers to the negative value of the natural logarithm of the internal transmittance of natural light passing through the glass sheet per centimeter. When the incident light is vertically incident on the glass sheet, the light intensity is attenuated due to the absorption of the glass sheet. The light absorption coefficient value can be calculated by measuring the natural light transmittance of the glass sheet. Specifically, the light absorption coefficient can be calculated using the following formula:

[0027]

[0028] K is the light absorption coefficient of the glass sheet, l is the thickness of the glass sheet in the stacking direction; n is the refractive index of the glass sheet for lasers of a specific wavelength, and T is the transmittance of the glass sheet to lasers of a specific wavelength.

[0029] The total forming temperature (i.e., the hot bending forming temperature) in the forming method of the present invention is approximately in the range of 577-688°C, further in the range of 582-683°C, which is generally higher than the existing automotive glass forming temperature by more than 10°C, further higher than the existing automotive glass forming temperature by more than 13°C, and further higher than the existing automotive glass forming temperature by more than 15°C. The above-mentioned forming temperature range is applicable to the heat forming of glass sheets with a thickness of less than 2.1 mm.

[0030] In the above molding method, the total time of the heating treatment is generally controlled to be 2-5 minutes. If the heating time is too short, the molding will fail; if the heating time is too long, it will cause defects such as burns and distortion on the glass surface, left and right deviation during the transmission of the original glass sheet, and serious optical deformation. What's more, it cannot be transmitted normally, resulting in furnace driving accidents, etc.

[0031] In the above-mentioned forming method, along the sheet-in-and-out end of the heating furnace (i.e., along the transmission direction of the original glass sheet from entering the furnace to exiting the furnace), the heating zones in the heating furnace are the first zone, the second zone, the third zone, the fourth zone, the fifth zone, the sixth zone, the seventh zone, the eighth zone, and the ninth zone, which are connected in sequence. From the first zone to the ninth zone, the heating temperature gradually increases. Among them, the first zone, the second zone, and the third zone can be called the first three zones, the fourth zone, the fifth zone, and the sixth zone can be called the middle three zones, and the seventh zone, the eighth zone, and the ninth zone can be called the last three zones. From the first zone to the ninth zone, the heating temperature gradually increases. Specifically, from the first zone to the seventh zone, the heating temperature gradually increases, the heating temperature of the eighth zone is similar to that of the seventh zone, and the temperature of the ninth zone is the same as or similar to that of the eighth zone.

[0032] According to a specific embodiment of the present invention, the heating temperatures of the first zone, the second zone and the third zone can be controlled to be 592°C-647°C, for example, 592°C, 594°C, 597°C, 600°C, 610°C, 620°C, 630°C, 640°C, 642°C, 647°C and other specific values, and ranges with any two of the above specific values ​​as endpoints. Further, the heating temperatures of the first zone, the second zone and the third zone can be controlled to be 594°C-645°C, and further can be controlled to be 597°C-642°C.

[0033] According to a specific embodiment of the present invention, the heating temperatures of the fourth zone, the fifth zone and the sixth zone can be controlled to be 630-668°C, for example, specific values ​​such as 630°C, 640°C, 650°C, 660°C, 668°C, and ranges with any two of the above specific values ​​as endpoints. Further, the heating temperatures of the fourth zone, the fifth zone and the sixth zone can be controlled to be 632-666°C, and further can be 635-663°C.

[0034] According to a specific embodiment of the present invention, the heating temperatures of the seventh zone, the eighth zone and the ninth zone can be controlled to be 648-677°C, for example, specific values ​​such as 648°C, 650°C, 660°C, 670°C, 674°C, 677°C, 679°C, and ranges with any two of the above specific values ​​as endpoints. Further, the heating temperatures of the seventh zone, the eighth zone and the ninth zone can be controlled to be 650-675°C, and further can be 653-672°C.

[0035] According to a specific embodiment of the present invention, the top heating temperature of each heating section and each heating zone is generally higher than the bottom heating temperature. In some specific embodiments, each heating section and each heating zone in the heating furnace is provided with heating devices at the top and bottom, and the top heating temperature and the bottom heating temperature of each heating section and each heating zone can be controlled separately. In the present invention, the distance between the heating device at the top of the same heating zone and the glass original sheet is greater than the distance between the heating device at the bottom and the glass original sheet. Accordingly, by controlling the top heating temperature of the same heating zone to be higher than the bottom heating temperature, it can be ensured that the upper and lower surfaces of the glass original sheet are heated evenly.

[0036] The height of each heating zone is denoted as h, and the glass sheet is located on the midline of the height direction of the heating zone. The "top" refers to the area above the glass sheet and whose vertical distance to the glass sheet is greater than 0 and less than or equal to 50% h; the "bottom" refers to the area below the glass sheet and whose vertical distance to the glass sheet is greater than 0 and less than or equal to 20% h.

[0037] In the above-mentioned forming method, heating equipment is respectively provided on the left side, the middle and the right side of the top and bottom of each heating zone. Then each heating zone has a heating temperature of the left side of the top, a heating temperature of the middle of the top, a heating temperature of the right side of the top, a heating temperature of the left side of the bottom, a heating temperature of the middle of the bottom and a heating temperature of the right side of the bottom, and the heating temperatures of the above-mentioned positions can be controlled separately. Among them, the length of a heating zone is d, and "middle" refers to the position of the center line of each heating zone (the center line perpendicular to the transportation direction of the original glass sheet, that is, the center line of the length direction of the heating zone): "left side" refers to the area located on the left side of the center line of the heating zone, and the horizontal distance from the center line is greater than 0 and less than or equal to 30% d; "right side" refers to the area located on the right side of the center line of the heating zone, and the horizontal distance from the center line is greater than 0 and less than or equal to 30% d.

[0038] In the above molding method, the top heating temperatures of the first zone, the second zone and the third zone can be controlled to be 597-647°C, for example, specific values ​​such as 597°C, 599°C, 600°C, 602°C, 610°C, 620°C, 630°C, 640°C, 642°C, 645°C, 647°C and the like, and ranges with any two of the above specific values ​​as endpoints. Further, the top heating temperatures can be controlled to be 599-645°C, and further, the top heating temperatures can be controlled to be 602-642°C.

[0039] In the above molding method, the bottom heating temperatures of the first zone, the second zone and the third zone can be controlled to be 592-641°C, for example, specific values ​​such as 592°C, 594°C, 600°C, 610°C, 620°C, 630°C, 639°C, 640°C, 641°C, and ranges with any two of the above specific values ​​as endpoints. Further, they can be controlled to be 594-639°C, and further, 597-636°C.

[0040] In the above molding method, the top heating temperatures of the fourth zone, the fifth zone and the sixth zone can be controlled to be 634-668°C, for example, specific values ​​such as 634°C, 636°C, 639°C, 640°C, 650°C, 660°C, 663°C, 666°C, 668°C, and ranges with any two of the above specific values ​​as endpoints. Further, the top heating temperatures of the fourth zone, the fifth zone and the sixth zone can be controlled to be 636°C-666°C, and further, 639-663°C.

[0041] In the above molding method, the bottom heating temperatures of the fourth zone, the fifth zone and the sixth zone can be controlled to be 630-663°C respectively; for example, they can be 630°C, 632°C, 635°C, 640°C, 650°C, 658°C, 660°C, 661°C, 663°C and other specific values, and ranges with any two of the above specific values ​​as endpoints. They can be further controlled to be 632-661°C, and further controlled to be 635-658°C.

[0042] In the above molding method, the top heating temperatures of the seventh zone, the eighth zone and the ninth zone can be controlled to be 652-677°C, for example, specific values ​​such as 652°C, 654°C, 657°C, 660°C, 670°C, 672°C, 675°C, 677°C and the like, and ranges with any two of the above specific values ​​as endpoints. Further, the temperatures can be controlled to be 654-675°C, and further, the temperatures can be controlled to be 657-672°C.

[0043] In the above molding method, the bottom heating temperature of the seventh zone, the eighth zone and the ninth zone can be controlled to be 648-673°C, for example, specific values ​​such as 648°C, 650°C, 653°C, 660°C, 668°C, 670°C, 671°C, 673°C and the like, and a range with any two of the above specific values ​​as endpoints. Further, it can be 650-671°C, and further, it can be 653-668°C.

[0044] In some specific embodiments, the heating device may be a heating wire. Specifically, at least a heating wire is provided at the top and bottom of each heating zone; further, heating wires are provided at the top left side, the top middle, the top right side, the bottom left side, the bottom middle, and the bottom right side of each heating zone. The heating temperature at each position of each heating zone may be the temperature of the heating wire. The heating wires of each heating zone can heat the original glass sheet at the same time.

[0045] The heating furnace of the present invention heats the original glass sheet from the top, bottom, left side, middle and right side of the same heating zone at the same time, which can ensure that each position of the original glass sheet is heated evenly (including between the upper surface and the lower surface of the original glass sheet, between the large end, the middle and the small end of the glass), thereby achieving better microscopic optical performance, and performing microscopic optical detection with the help of a refracting plate, a moiré scanner, etc., so as to meet the optical requirements of the automobile windshield. By adopting the above heating method and controlling the molding temperature within an appropriate range, the glass can have a moderate viscosity, so that it can flow and form without causing shape instability due to excessive flow, which is conducive to the subsequent pressing and molding stage. The original glass sheet is closely fitted with the concave mold and the convex mold to obtain a better processing effect.

[0046] In the molding method provided by the present invention, the heating temperatures of the front three zones, the middle three zones and the rear three zones are respectively higher than the heating temperatures of the front three zones, the middle three zones and the rear three zones of the existing molding method. By adjusting the heating temperature, the optical properties of the molded glass can be significantly improved, especially the microscopic optical properties of the molded glass (for example, light distortion can be significantly reduced). In addition, the present invention can make the curvature of the glass bend just meet the requirements by controlling the average heating temperature of each of the front three zones, the middle three zones and the rear three zones within a certain range. In some specific embodiments, for the glass original sheet used for the side window glass, the curvature range of the glass original sheet after heating treatment can meet the following requirements: the radius of curvature ≥ 1000mm; for the glass original sheet used for the front windshield, the curvature range of the glass after heating treatment can meet the following requirements: the radius of curvature is 200-3000mm.

[0047] According to a specific embodiment of the present invention, the average heating temperature of the first three zones in the molding method of the present invention is more than 23°C higher than the average heating temperature of the first three zones in the existing automotive glass original sheet molding method. The glass original sheet used in the present invention has a high softening point, and the corresponding molding temperature is also high. By controlling the average heating temperature of the first three zones in the molding method within a certain range, the curvature of the glass bending can just meet the requirements. For example, the average value of the top middle heating temperature of the first three zones in the existing molding method for green glass original sheets is 607°C, and the average value of the top middle heating temperature of the first three zones in the molding method of the present invention can be 630°C, which is 23°C higher than the average value of the heating temperature at the same position in the existing molding method.

[0048] Furthermore, in the molding method of the present invention, the top heating temperature of the first three zones is higher than the bottom heating temperature by more than 5°C.

[0049] In the above molding method, the top heating temperature of the first zone is 597-632°C, further can be 599-630°C, further can be 602-627°C; the bottom heating temperature of the first zone is 592-621°C, further can be 594-613°C, further can be 597-616°C.

[0050] In the above molding method, the top heating temperature of the second zone is 611-639°C, further can be 613-637°C, further can be 616-634°C; the bottom heating temperature of the second zone is 605-629°C, further can be 607-627°C, further can be 610-624°C.

[0051] In the above molding method, the top heating temperature of the third zone is 625-647°C, further can be 627-645°C, further can be 630-642°C; the bottom heating temperature of the third zone is 613-641°C, further can be 615-639°C, further can be 618-636°C.

[0052] According to a specific embodiment of the present invention, the average heating temperature of the middle three zones of the inventive molding method is more than 17° C. higher than the average heating temperature of the middle three zones of the existing automotive glass raw sheet molding method.

[0053] Furthermore, in the molding method of the invention, the top heating temperature of the middle three zones is higher than the bottom heating temperature by more than 4°C.

[0054] In the above molding method, the top heating temperature of the fourth zone is 634-664°C, further can be 636-662°C, further can be 639-659°C; the top heating temperature of the fourth zone is 630-651°C, further can be 632-649°C, further can be 635-646°C.

[0055] In the above molding method, the top heating temperature of the fifth zone is 643-666°C, further can be 645-664°C, further can be 648-661°C; the bottom heating temperature of the fifth zone is 635-662°C, further can be 637-660°C, further can be 640-657°C.

[0056] In the above molding method, the top heating temperature of the sixth zone is 646-668°C, further can be 648-660°C, further can be 651-663°C; the bottom heating temperature of the sixth zone is 640-663°C, further can be 642-661°C, further can be 645-658°C.

[0057] According to a specific embodiment of the present invention, the average heating temperature of the last three zones of the inventive molding method is more than 5° C. higher than the average heating temperature of the last three zones of the existing automobile glass original sheet molding method.

[0058] Furthermore, in the molding method of the invention, the top heating temperature of the last three zones is higher than the bottom heating temperature by more than 3°C.

[0059] In the above molding method, the top heating temperature of the seventh zone is 652-674°C, further can be 654-672°C, further can be 657-669°C; the bottom heating temperature of the seventh zone is 640-667°C, further can be 642-665°C, further can be 645-662°C.

[0060] In the above molding method, the top heating temperature of the eighth zone is 656-676°C, further can be 658-674°C, further can be 661-671°C; the bottom heating temperature of the eighth zone is 653-673°C, further can be 655-671°C, further can be 658-668°C.

[0061] In the above molding method, the top heating temperature of the ninth zone is 656-677°C, further can be 658-675°C, further can be 661-672°C; the bottom heating temperature of the ninth zone is 653-673°C, further can be 655-671°C, further can be 658-668°C.

[0062] Furthermore, in the forming method of the present invention, the heating temperature at the same height of each heating zone can be symmetrically distributed along the center line so that the surface of the original glass sheet is heated evenly.

[0063] According to a specific embodiment of the present invention, the heating furnace may include at least one of a single-piece pressing and forming furnace, a self-weight baking and bending forming furnace, a double-piece pressing and forming furnace, and the like.

[0064] According to a specific embodiment of the present invention, the original glass sheet after being treated in the heating furnace is generally sent from the sheet outlet end of the heating furnace (the ninth zone) to the forming section outside the furnace for press forming to form the high-transmittance glass.

[0065] According to a specific embodiment of the present invention, in the first to ninth zones, the length of each heating zone is generally 1500-4000 mm. Among them, the first to eighth zones are usually used as heating zones, and their main functions are to heat the original glass sheet (the first to seventh zones) and keep it warm (the eighth zone); the ninth zone is used as a heating transmission zone, in addition to maintaining the heating temperature of the original glass sheet (similar to or basically the same as the heating temperature of the eighth zone), it is also used to transport the original glass sheet to the forming section. Correspondingly, the transmission speed of the glass sheet in the first zone to the eighth zone can be 50-300mm / s, for example, 50mm / s, 100mm / s, 150mm / s, 200mm / s, 250mm / s, 300mm / s and other specific values, and a range with any two of the above specific values ​​as endpoints; the glass sheet is transmitted at a uniform speed in the ninth zone, and the transmission speed in the ninth zone is faster than that in the first eight zones. Specifically, the transmission speed of the glass sheet in the ninth zone can be 800-1500mm / s, for example, 800mm / s, 900mm / s, 1000mm / s, 1100mm / s, 1200mm / s, 1300mm / s, 1400mm / s, 1500mm / s and other specific values, and a range with any two of the above specific values ​​as endpoints. In a specific embodiment, the transmission speed of the glass sheet in each heating zone can be adjusted according to the actual thickness of the glass sheet. For example, for a glass sheet with a thicker thickness, it can be transmitted at a lower transmission speed and the heating temperature can be increased to ensure that the glass sheet is fully heated.

[0066] According to a specific embodiment of the present invention, the press molding process may include: sending the heated glass sheet to a molding section having a concave mold and a convex mold, using the concave mold to lift the glass sheet until the upper surface of the glass sheet contacts the convex mold, and the glass sheet contacts the concave mold and the convex mold at the same time and is pressed; after the pressing is completed, the convex mold sucks the glass sheet up, and then the transmission shuttle of the molding section extends to the bottom of the convex mold and the glass sheet, and after the travel of the transmission shuttle is in place, the convex mold and the glass sheet are separated, and the glass sheet falls on the transmission shuttle and is transmitted by the transmission shuttle to the annealing area for annealing to complete the press molding.

[0067] In the above pressing and forming process, the concave mold in the forming section is located below the original glass sheet, and the concave surface is a quadrilateral mold frame structure. The concave mold is in contact with the periphery of the original glass sheet.

[0068] In the above molding process, the convex mold in the molding section is located above the original glass sheet and has an arc-shaped surface, which can contact the entire upper surface of the original glass sheet. Furthermore, the surface of the convex mold can have a plurality of (more than two) small holes regularly distributed, and the aperture of the small holes is generally less than 5 mm. Through the above small holes, the convex mold can vacuum absorb the original glass sheet and move it.

[0069] In the above-mentioned pressing process, the time when the glass sheet is in contact with the concave mold and the convex mold at the same time (i.e., the molds are closed) is the pressing time, and the pressing time is generally less than 2 seconds.

[0070] The present invention also provides a high-transmittance (SuperClear-Light, SC-L for short) glass, which is obtained by forming by the above forming method.

[0071] According to a specific embodiment of the present invention, the thickness of the high-transmittance glass is generally less than 2.1 mm, and further the thickness may be less than 1.8 mm, for example, 1.3-1.6 mm. When the glass thickness is reduced to less than 1.8 mm, relative to the thickness of ordinary automobile glass of about 2.1 mm, the high-transmittance glass provided by the present invention has a reduced thickness and has the characteristics of being lightweight, while maintaining good optical properties and mechanical strength, and can meet the requirements for lightweight in the field of automobile manufacturing.

[0072] In some specific embodiments, the transmittance of a glass sheet with a thickness of 1.3-2.1 mm for light with a wavelength of 800-1600 nm is above 91%, and the high-transmittance glass made from the glass sheet by the molding method of the present invention also maintains the above transmittance. The transmittance of the high-transmittance glass (thickness 1.3-2.1 mm) for light with a wavelength of 800-1600 nm is above 91.3% (≥91.3%).

[0073] In some specific embodiments, the glass substrate having a thickness of 1.3-2.1 mm has a light absorption coefficient of 0.04-0.2 cm for light with a wavelength of 800-1600 nm. -1 , can further reach 0.04-0.11cm -1 The high-transmittance glass made by the molding method of the present invention using the original glass sheet can also maintain the performance of low absorption. The light absorption coefficient of the high-transmittance glass for light with a wavelength of 800-1600nm is 0.04-0.2cm -1 , can further reach 0.04-0.11cm -1 .

[0074] The high-transmittance glass has high transmittance and low absorption in the near-infrared band, which can meet the requirements of optical sensors such as LiDAR and infrared cameras for glass transmittance in this band, and can thus be used to make functional integrated glass.

[0075] In some specific embodiments, the high-transmittance glass has high wear resistance. Specifically, the wear resistance is characterized by haze. After the ordinary glass original sheet is subjected to abrasion treatment by a rotary abraser (the conditions are load weight 4.9N, grinding number 2000 revolutions), the haze of ordinary glass (such as existing ultra-white glass) before abrasion treatment is ≤0.5%, and the haze after abrasion treatment is ≤1%. The haze of the high-transmittance glass of the present invention before abrasion treatment is ≤0.1%, and the haze after abrasion treatment can be controlled to ≤0.2%, showing a high ability to resist abrasion.

[0076] In some specific embodiments, the high-transmittance glass has a high ability to resist scratches. Specifically, the Vickers hardness of the high-transmittance glass can reach 610HV or more. Compared with the Vickers hardness of the existing ultra-white glass of 550±10HV, the Vickers hardness of the high-transmittance glass of the present invention is increased by more than 8%. The high-transmittance glass of the present invention has a high hardness, correspondingly a long service life and better durability, and can be used to manufacture windshield glass built into LiDAR.

[0077] In some specific embodiments, the optical distortion of the high-transmittance glass and / or the laminated glass made of the high-transmittance glass is ≤150mdpt; the tensile stress of the high-transmittance glass and / or the laminated glass made of the high-transmittance glass is <12MPa, and the edge compressive stress of the high-transmittance glass and / or the laminated glass made of the high-transmittance glass is >12MPa. The laminated glass may include two layers of the above-mentioned high-transmittance glass, and a bonding layer such as PVB (polyvinyl butyral) is sandwiched between the two glass plates. In some specific embodiments, the thickness of the high-transmittance glass in the laminated glass may be less than 2.1mm, and the bonding layer may be 0.76mm.

[0078] In some specific embodiments, the refractive index, conformity and other parameters of the laminated glass made of the high-transmittance glass meet the requirements of GB9656-2003 "Automobile Safety Glass".

[0079] The present invention also provides a laminated glass, which comprises an outer glass plate, an inner glass plate and an adhesive layer, wherein the adhesive layer is located between the outer glass plate and the inner glass plate; the outer glass plate and / or the inner glass plate is the above-mentioned high-transmittance glass.

[0080] In some specific embodiments, the material of the adhesive layer may include PVB, etc. The thickness of the adhesive layer may be less than 0.8 mm, for example, 0.76 mm.

[0081] In some specific embodiments, the total thickness of the laminated glass is generally less than 4 mm.

[0082] In some specific embodiments, by using thinner high-transmittance glass as the outer glass plate and the inner glass plate, the laminated glass formed has low thickness and light weight, while maintaining high optical performance and mechanical strength, and significantly improving the ability to resist scratches and wear. For example, the mechanical strength of the laminated glass formed by using 1.6mm thick high-transmittance glass as the inner glass plate and the outer glass plate is basically equivalent to that of the laminated glass using 2.1mm thick ordinary glass as the inner and outer glass plates, but the weight is reduced by more than about 20%, and the total thickness of the laminated glass is reduced from 4.96mm to 3.96mm.

[0083] In some specific embodiments, the inner glass plate and the outer glass plate may both be the above-mentioned high-transmittance glass provided by the present invention, or may be a combination of high-transmittance glass and ordinary glass plate (white glass, green glass, dark green glass). Preferably, the inner glass plate and the outer glass plate may both be high-transmittance glass; further, high-transmittance glass of the same thickness may be used so that the same heating temperature parameters may be used for molding processing, which is convenient for production control, conducive to yield rate, production frequency and beat control, and convenient for mass production.

[0084] In some specific embodiments, the composition of the inner glass plate and the outer glass plate can be the same or different, preferably the same. The inner glass plate and the outer glass plate can be made of high-transmittance glass with the same composition.

[0085] In some specific embodiments, the thickness of the inner glass plate and the outer glass plate can be the same or different. For example, the inner glass plate and the outer glass plate can be selected from the following high-transmittance glass thicknesses: 1.3 mm high-transmittance glass, 1.4 mm high-transmittance glass, 1.5 mm high-transmittance glass, 1.6 mm high-transmittance glass, 1.7 mm high-transmittance glass, 1.8 mm high-transmittance glass, etc., 2.1 mm high-transmittance glass.

[0086] The present invention also provides a vehicle window glass, which is made of the above-mentioned high-transmittance glass. In some specific embodiments, the vehicle window glass can be a front windshield, a rear windshield, a side window glass, a skylight glass, etc. The high-transmittance glass provided by the present invention has a high optical transmittance in the near-infrared band, which can meet the requirements of optical sensors such as LiDAR and infrared cameras for glass transmittance, and can be used to make functional integrated vehicle window glass, such as a functional integrated front windshield.

[0087] In addition, the laminated glass provided by the present invention can maintain a high level of optical performance and mechanical strength while reducing thickness and weight, and has high resistance to scratches and abrasions, thus meeting the lightweight requirements of automobile manufacturing.

[0088] The beneficial effects of the present invention include:

[0089] The high-transmittance glass provided by the present invention is light in weight, low in absorption and has high light transmittance, especially in the 800-1600nm optical band, with high optical transmittance; it has high mechanical strength, scratch resistance and wear resistance. The low-absorption high-transmittance glass can meet the light transmittance requirements of optical sensors and can be used for functional integrated glass, such as the front windshield of LiDAR built-in products. DETAILED DESCRIPTION

[0090] In order to have a clearer understanding of the technical features, purposes and beneficial effects of the present invention, the technical solution of the present invention is now described in detail below, but it should not be construed as limiting the applicable scope of the present invention.

[0091] Example 1

[0092] This embodiment provides a method for forming high-transmittance glass, the method comprising:

[0093] S1, sending the original glass sheet into a heating furnace for heating treatment;

[0094] S2. The glass sheet that has been heated is transferred from the heating furnace to the forming section for pressing and forming to obtain high-transmittance glass, which is recorded as SC-L glass.

[0095] The glass sheet used in this embodiment is a medium aluminum glass sheet, the aluminum content of the glass sheet is 4-5wt%, the iron content is less than 150ppm (it can further be less than 130ppm, or less than 110ppm, or less than 90ppm); the softening point of the glass sheet is 747±5℃, the annealing point is 560±10℃. The thickness of the glass sheet is less than 2.1mm.

[0096] The heating furnace used in this embodiment is a single-piece pressing furnace.

[0097] The heating furnace is equipped with a preheating section, a heating section and a constant temperature gradient section. Specifically, there are 9 heating zones in the heating furnace. The original glass sheet is conveyed from left to right. The heating zones are the first zone, the second zone, the third zone, the fourth zone, the fifth zone, the sixth zone, the seventh zone, the eighth zone and the ninth zone from left to right. The heating temperature of the first zone to the ninth zone gradually increases. Among them, the first zone to the third zone are the preheating section, the fourth zone to the seventh zone are the heating section, and the eighth zone and the ninth zone are the constant temperature gradient section.

[0098] The top and bottom of each heating zone are respectively provided with heating wires as heating devices; the heating temperature at the top of the same heating zone is higher than the heating temperature at the bottom.

[0099] Heating wires are provided at the left, middle and right sides of the same height. That is, each heating zone is provided with heating wires at the left side of the top, the middle of the top, the right side of the top, the left side of the bottom, the middle of the bottom and the right side of the bottom. The temperature of each heating wire is independently controlled, and the heating wires in each heating zone can heat the original glass sheet at the same time.

[0100] Among them, the height of each heating zone is denoted as h, the glass sheet is located on the midline of the height direction of the heating zone, the "top" refers to the area above the glass sheet, and the vertical distance to the glass sheet is greater than 0 and less than or equal to 50% h; the "bottom" refers to the area below the glass sheet, and the vertical distance to the glass sheet is greater than 0 and less than or equal to 20% h.

[0101] Let the length of each heating zone be d, and the corresponding area ranges of the middle, left and right sides at the same height are as follows: "middle" refers to the area located on the midline of the length direction of the heating zone, "left side" refers to the area located on the left side of the midline in the length direction, and the horizontal distance from the midline is greater than 0 and less than or equal to 30% d; "right side" refers to the area located on the right side of the midline in the length direction, and the horizontal distance from the midline is greater than 0 and less than or equal to 30% d.

[0102] The heating temperatures at each position in each heating zone in S1 are shown in Table 1.

[0103] The molding section for performing press molding in S2 includes a punch, a die, and a transfer shuttle.

[0104] The convex mold is located above the original glass sheet and has an arc-shaped surface that can contact the entire upper surface of the original glass sheet. The surface of the convex mold may have a number (more than two) of small holes regularly distributed, and the aperture of the small holes is generally less than 5 mm. Through the above-mentioned small holes, the convex mold can vacuum absorb the original glass sheet to make it move.

[0105] The concave mold is located below the original glass sheet, and the concave surface is a quadrilateral mold frame structure. The concave mold is in contact with the periphery of the original glass sheet.

[0106] The pressing process of S2 specifically includes: using the concave mold to lift the glass sheet until the upper surface of the glass sheet contacts the convex mold, the glass sheet contacts the concave mold and the convex mold at the same time (i.e., the molds are closed) and pressed, the pressing temperature is controlled to be lower than the heating temperature of the fourth to ninth zones in the heating furnace, and the pressing time is controlled to be less than 2 seconds; after the pressing is completed, the convex mold sucks the glass sheet to form an upward movement, and then the transmission shuttle extends to the bottom of the convex mold and the glass sheet. After the travel of the transmission shuttle is in place, the convex mold and the glass sheet are separated, and the glass sheet falls on the transmission shuttle and is transmitted by the transmission shuttle to the annealing area for annealing (annealing temperature is 520-620℃, annealing time is 10min-35min), completing the pressing and molding.

[0107] Comparative Example 1

[0108] This comparative example provides a method for forming a green glass raw sheet, which includes sending the green glass raw sheet into a heating furnace for heating treatment, and then sending it to a forming section for press forming after it is output from the heating furnace to obtain green glass, which is recorded as G glass.

[0109] The glass sheet used in this comparative example is a green glass sheet, and the iron content of the glass sheet is about 800-900 ppm; the softening point of the glass sheet is 725-730°C, and the annealing point is 560-620°C.

[0110] The heating furnace used in this comparative example is the same as that in Example 1, and the distribution of each heating zone and the distribution of the heating furnace wires are also the same as those in Example 1.

[0111] The heating temperatures at each position of each heating zone are shown in Table 1 (the numerical unit in the table is °C). "Upper left" represents the heating temperature of the left side of the top, "Upper middle" represents the heating temperature of the middle of the top, "Upper right" represents the heating temperature of the right side of the top, "Lower left" represents the heating temperature of the left side of the bottom, "Lower middle" represents the heating temperature of the middle of the bottom, and "Lower right" represents the heating temperature of the right side of the bottom. The temperatures in Table 1 are the readings of the thermocouple temperatures.

[0112] Table 1

[0113]

[0114] It can be seen from Table 1 that the molding temperature of the existing green glass raw sheet is 576-658° C., the molding temperature of the high-transmittance glass of the present invention is 606-672° C., and the molding temperature of the molding method provided by the present invention is higher.

[0115] Example 2

[0116] This embodiment provides a method for forming high-transmittance glass, the method comprising:

[0117] S1, sending the original glass sheet into a heating furnace for heating treatment;

[0118] S2. The glass sheet that has been heated is transferred from the heating furnace to the forming section for pressing and forming to obtain high-transmittance glass, which is recorded as SC-L glass.

[0119] The glass sheet used in this embodiment is a medium aluminum glass sheet, the aluminum content of the glass sheet is 4-5wt%, the iron content is less than 150ppm (it can further be less than 130ppm, or less than 110ppm, or less than 90ppm); the softening point of the glass sheet is 747±5℃, the annealing point is 560±10℃. The thickness of the glass sheet is 1.3mm.

[0120] The molding method of this embodiment is similar to the molding method of embodiment 1, except that the temperature of the heating treatment in S1 is different. The heating temperatures of each heating zone at each position in this embodiment are shown in Table 2 (the numerical unit in the table is: ° C). The temperatures in Table 2 are the readings of the thermocouple temperatures.

[0121] Table 2

[0122]

[0123] Compared with the forming temperature of 1.6 mm thick SC-L glass in Example 1, the forming temperature of 1.3 mm SC-L glass is low, the transmission speed of the glass from the first zone to the eighth zone is similar, and the transmission speed of the ninth zone is faster than that of the first eight zones. It can be seen that the temperature pattern of each heating zone is as follows: the forming temperature gradually increases from the first zone to the eighth zone; the ninth zone plays the role of a heat preservation transmission zone, and the temperature is similar to that of the eighth zone.

[0124] Example 3

[0125] This embodiment provides a laminated glass, which is composed of an outer glass plate, an inner glass plate and an adhesive layer, wherein the adhesive layer is located between the outer glass plate and the inner glass plate.

[0126] The outer glass plate and the inner glass plate are respectively the high-transmittance glass SC-L prepared in Example 1; and the material of the bonding layer is transparent PVB.

[0127] Comparative Example 2

[0128] This comparative example provides a laminated glass, whose structure is similar to that of the laminated glass of Example 3, except that: the outer glass plate and the inner glass plate of the laminated glass of this comparative example are respectively the green glass prepared in Comparative Example 1.

[0129] Example 4

[0130] This embodiment provides a laminated glass, and its structure is similar to that of the laminated glass of Embodiment 3, except that: the outer glass plate and the inner glass plate of the laminated glass of this embodiment are respectively the high-transmittance glass prepared in Embodiment 2.

[0131] Test Example 1

[0132] The laminated glasses of Example 3 and Comparative Example 2 were subjected to performance tests, and the test results are summarized in Table 3.

[0133] The composition of the laminated glass to be tested in Example 3 is as follows: the thickness of the high-transmittance glass is 1.6 mm, the aluminum content of the corresponding glass sheet is 4.69 wt%, the iron content is 105 ppm, the softening point is 748°C, and the annealing point is 561°C; the thickness of the adhesive layer is 0.76 mm. The light absorption coefficient of the glass sheet is 0.11 cm -1 .

[0134] The composition of the laminated glass to be tested in Comparative Example 2 is as follows: the thickness of the green glass is 1.6 mm, the iron content of the corresponding green glass original sheet is 805 ppm, the softening point is 728°C, and the annealing point is 592°C; the thickness of the adhesive layer is 0.76 mm. The light absorption coefficient of the green glass is 3.76 cm -1 .

[0135] The test method is as follows:

[0136] Light absorption coefficient:

[0137] The laser wavelength used for the light absorption coefficient is 800-1600nm, and the calculation formula for the light absorption coefficient is:

[0138]

[0139] K is the light absorption coefficient of the glass sheet, l is the thickness of the glass sheet in the stacking direction; n is the refractive index of the glass sheet for lasers of a specific wavelength, and T is the transmittance of the glass sheet to lasers of a specific wavelength.

[0140] Resistance to scratches and abrasion, Vickers hardness:

[0141] The ability to resist scratches and wear is characterized by Vickers hardness. The test method is to place a non-deformed Vickers indenter made of diamond in the shape of a regular tetrahedron on the surface of the glass sample, follow a specified trajectory and keep it for a specified time to form an indentation, and the load is divided by the value obtained by dividing the indentation surface area calculated based on the average diagonal length of the indentation. It is expressed in dimensionless units HV. For specific operating steps and precautions, please refer to GB / T16534-2009 "Test Method for Room Temperature Hardness of Fine Ceramics".

[0142] The instrument used is LD-XV1000A micro Vickers hardness tester.

[0143] After testing, the Vickers hardness of the original glass of the present invention is above 610HV, and the Vickers hardness of the formed high-transmittance glass has no significant change and is also above 610HV. In comparison, the Vickers hardness of the original glass of common automobiles is 550±10HV. It can be seen that the hardness of the glass of the present invention is 8% higher than that of the common automobile glass, and has a longer service life and better durability.

[0144] Abrasion resistance:

[0145] The abrasion resistance test method uses the Taber 1700 rotary abraser. The grinding wheel load is 4.9N, the grinding revolution is 2000 revolutions, and the test surface is the outer surface of the glass (facing the outside of the vehicle). The haze value caused by abrasion is obtained by subtracting the initial haze value from the final haze value. For details, see GB / T 5137.1-2020 "Test methods for automotive safety glass Part 1: Mechanical properties test" pages 5-9.

[0146] The glass sheet used in the present invention has a haze of ≤0.1% before the wear test. After the wear test method, the haze of the glass sheet is ≤0.2%. The high-transmittance glass formed by using the glass sheet also has the same wear resistance (haze before the wear test is ≤0.1%, haze after the wear test is ≤0.2%). For comparison, the haze of common automobile glass is ≤1%. It can be seen that the haze of the glass sheet and the formed high-transmittance glass of the present invention after the wear treatment is lower, indicating that the wear resistance of the high-transmittance glass formed by the present invention is better than that of common automobile glass.

[0147] Impact resistance:

[0148] The test method is: using a hardened steel ball with a mass of 227±2g and a diameter of about 38mm. The purpose of the test is to determine whether the laminated glass has a certain minimum strength or adhesion under the impact of a small hard object. The sample size is 300*300mm. During the high temperature test, the temperature is kept at 40±2℃ for at least 4h and the impact height is 9m; during the low temperature test, the temperature is kept at -20±2℃ for at least 4h and the impact height is 8.5m. The surface of the sample impacted by the steel ball is the outer surface of the automobile glass after installation, and only one impact is made. After the impact, the form and degree of damage of the sample are evaluated. If there are requirements for the quality of the peeling fragments on the reverse side of the impact surface, the total mass of the peeling fragments should also be weighed and recorded. The mass of the peeling fragments on the reverse side is ≤20g, which is up to standard. For details, see GB / T 5137.1-2020 "Test methods for automotive safety glass Part 1: Mechanical properties test" pages 1-4.

[0149] Penetration resistance:

[0150] A hardened steel ball with a mass of 2260±20g and a diameter of about 82mm is used. The purpose of the test is to evaluate the penetration resistance of laminated safety glass. The sample size is 300*300mm. The surface of the sample impacted by the steel ball is the inner surface of the automobile glass after installation, and it is impacted only once. After the impact, it is evaluated whether the steel ball penetrates the sample within 5s. If it does not penetrate the sample within 5s, it is considered "up to standard". For details, see GB / T 5137.1-2020 "Test methods for automobile safety glass Part 1: Mechanical properties test" pages 4-5.

[0151] Human head model impact:

[0152] The human head model is spherical or hemispherical, made of laminated hardwood, with a replaceable felt cap and a wooden crossbeam. The thickness of the felt cap is 5±1mm, and the total mass of the human head model is 10±0.2kg. The front windshield laminated safety glass product is placed freely on the bracket, and its impact surface should be the inner surface of the car glass after installation. Each specimen is allowed to be impacted only once. The impact height of the human head model is 1500mm, and the surface of the impact point area should be roughly perpendicular to the impact direction. After the impact, the radius of the annular crack, the exposed area of ​​the middle layer or the length of the crack, the mass of the peeling fragments, etc. are recorded. The standard for "compliance" after impact is that the radius of the annular crack is ≤40mm and the exposed area of ​​the middle layer (PVB) is ≤200mm 2 , the mass of peeling fragments is ≤20g. For details, see GB / T 5137.1-2020 "Test methods for automotive safety glass Part 1: Mechanical properties test", pages 11-13.

[0153] Table 3

[0154]

[0155] It can be seen from Table 3 that the laminated glass made of the high-transmittance glass provided by the present invention has comparable impact resistance, penetration resistance and safety to existing automotive glass while being lighter and thinner than existing automotive glass, and has significantly improved abrasion resistance and hardness.

[0156] The above test was performed on the laminated glass of Example 4, and the test results were:

[0157] Impact resistance: up to standard (19.6g);

[0158] Penetration resistance: up to standard (no penetration within 5 seconds);

[0159] Human head model impact: up to standard [annular crack radius ≤ 38.9mm, exposed area of ​​the middle layer (PVB) ≤ 191mm 2 , the mass of peeling fragments ≤ 18.3g];

[0160] Abrasion resistance: The haze after testing is 0.09%;

[0161] Vickers hardness: 611HV.

[0162] The laminated glass made of the SC-L high-transmittance glass of Example 1 in Example 3 has the following properties: optical distortion is 138mdpt; tensile stress is 11.1MPa, edge compressive stress is 15.9MPa; refraction, fit, etc. all meet the requirements of GB9656-2003.

[0163] The laminated glass made of the SC-L high-transmittance glass of Example 2 in Example 4 has the following properties: optical distortion is 129mdpt; tensile stress is 11.6MPa, edge compressive stress is 14.7MPa; refraction, fit, etc. all meet the requirements of GB9656-2003.

[0164] The light transmittance of the SC-L high-transmittance glass of Example 1 in the wavelength range of 800-1600nm is measured to be 91.6%, and the light transmittance of the SC-L high-transmittance glass of Example 2 in the wavelength range of 800-1600nm is 91.8%. The light absorption coefficient of the high-transmittance glass of Example 1 and Example 2 is 0.11cm -1 .

[0165] It can be seen from the above results that compared with the laminated glass made of ordinary green glass, the laminated glass made of the medium aluminum glass sheet of the present invention has a reduced thickness and a 20% weight reduction, while still having the required impact resistance, penetration resistance and human head model impact resistance, meeting the safety requirements of automotive glass; and, compared with ordinary green glass laminated glass, the laminated glass of the present invention has significantly improved wear resistance and hardness, better scratch resistance and wear resistance, longer service life and better durability; in addition, the laminated glass of the present invention has high optical transmittance in the near-infrared band, which can meet the optical requirements of optical sensors such as LiDAR for glass, and can be used in the manufacture of functional integrated vehicle window glass.

Claims

1. A method for forming high-transmittance glass, the method comprising: Placing the original glass sheet in a heating furnace for heating treatment, and then pressing and molding to obtain the high-transmittance glass; The heating furnace comprises a preheating section, a heating section, and a constant temperature gradient section connected in sequence; The inlet temperature of the preheating section is 592-632°C, and the outlet temperature of the preheating section is 613-647°C, and the outlet temperature of the preheating section is higher than the inlet temperature; The inlet temperature of the heating section is 630-664°C, the outlet temperature of the heating section is 648-674°C, and the outlet temperature of the heating section is higher than the inlet temperature; The temperature of the constant temperature gradient section is 653-677°C; The inlet temperature of the heating section is greater than or equal to the outlet temperature of the preheating section, and the inlet temperature of the constant temperature gradient section is greater than or equal to the outlet temperature of the heating section.

2. The molding method according to claim 1, wherein: The heating rate of the preheating section is 0.08-3.0°C / s; The heating speed of the heating section is greater than 0°C / s and less than or equal to 2.4°C / s.

3. The molding method according to claim 1 or 2, wherein: The heating furnace has 9 heating zones, which are the first zone to the ninth zone from the sheet inlet to the sheet outlet of the heating furnace, the first zone to the third zone are preheating sections, the fourth zone to the seventh zone are heating sections, and the eighth zone to the ninth zone are constant temperature gradient sections; From the first zone to the ninth zone, the heating temperature gradually increases; each heating zone heats the original glass sheet from above and below at the same time; Among them, the heating temperatures of the first zone, the second zone and the third zone are 592-647°C respectively, the heating temperatures of the fourth zone, the fifth zone and the sixth zone are 630-668°C respectively, and the heating temperatures of the seventh zone, the eighth zone and the ninth zone are 648-677°C respectively.

4. The molding method according to claim 3, wherein: The top heating temperature of the same heating zone is higher than the bottom heating temperature; The top heating temperatures of the first zone, the second zone and the third zone are 597-647°C, respectively, and the bottom heating temperatures of the first zone, the second zone and the third zone are 592-641°C, respectively; The top heating temperatures of the fourth zone, the fifth zone and the sixth zone are 634-668° C., respectively, and the bottom heating temperatures of the fourth zone, the fifth zone and the sixth zone are 630-663° C., respectively; The top heating temperatures of the seventh zone, the eighth zone and the ninth zone are 652-677°C, respectively, and the bottom heating temperatures of the seventh zone, the eighth zone and the ninth zone are 648-673°C, respectively.

5. The molding method according to claim 3, wherein: The top heating temperature of the first zone is 597-632°C, and the bottom heating temperature of the first zone is 592-621°C.

6. The molding method according to claim 3, wherein: The top heating temperature of the second zone is 611-639°C, and the bottom heating temperature of the second zone is 605-629°C.

7. The molding method according to claim 3, wherein: The top heating temperature of the third zone is 625-647°C, and the bottom heating temperature of the third zone is 613-641°C.

8. The molding method according to claim 3, wherein: The top heating temperature of the fourth zone is 634-664°C, and the top heating temperature of the fourth zone is 630-651°C.

9. The molding method according to claim 3, wherein: The top heating temperature of the fifth zone is 643-666°C, and the bottom heating temperature of the fifth zone is 635-662°C.

10. The molding method according to claim 3, wherein: The top heating temperature of the sixth zone is 646-668°C, and the bottom heating temperature of the sixth zone is 640-663°C.

11. The molding method according to claim 3, wherein: The top heating temperature of the seventh zone is 652-674°C, and the bottom heating temperature of the seventh zone is 640-667°C.

12. The molding method according to claim 3, wherein: The top heating temperature of the eighth zone is 656-676°C, and the bottom heating temperature of the eighth zone is 653-673°C.

13. The molding method according to claim 3, wherein: The top heating temperature of the ninth zone is 656-677°C, and the bottom heating temperature of the ninth zone is 653-673°C.

14. The molding method according to claim 3, wherein: The length of each heating zone is 1500-4000mm; The original glass sheet is uniformly transported in the first zone to the eighth zone, and the transport speed is 50-300 mm / s; The glass sheet is accelerated in the ninth zone at an acceleration of 800-1500 mm / s. 2 .

15. The molding method according to claim 1, wherein: The thickness of the original glass sheet is less than 2.1 mm; And / or, the light absorption coefficient of the glass sheet to light with a wavelength of 800-1600nm is 0.04-0.2cm -1 .

16. The molding method according to claim 1, wherein: The aluminum content of the glass raw sheet is 4-5wt%; The iron content of the glass raw sheet is ≤150ppm.

17. The molding method according to claim 1, wherein: The softening point temperature of the glass raw sheet is 742-752°C, and the annealing point temperature is 550-570°C.

18. A high-transmittance glass obtained by molding using the molding method according to any one of claims 1 to 17.

19. The high-transmittance glass according to claim 18, wherein: The transmittance of the high-transmittance glass to light with a wavelength of 800-1600nm is above 91.3%.

20. The high-transmittance glass according to claim 18, wherein: The haze of the high-transmittance glass is ≤0.1%; After being subjected to abrasion treatment with a load weight of 4.9N and a grinding rotation number of 2000 revolutions, the haze of the high-transmittance glass is ≤0.2%.

21. The high-transmittance glass according to claim 18, wherein: The optical distortion of the high-transmittance glass is ≤150mdpt; the tensile stress of the high-transmittance glass is <12MPa, and the edge compressive stress of the high-transmittance glass is >12MPa.

22. A laminated glass comprising an outer glass plate, an inner glass plate and an adhesive layer, wherein the adhesive layer is located between the outer glass plate and the inner glass plate; the outer glass plate and / or the inner glass plate is the high-transmittance glass according to any one of claims 18 to 21.

23. A vehicle window glass, which is made of the laminated glass according to claim 22.

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